The ghost that David Cameron fears the most passed briefly through the Commons chamber last week. Since his election as Conservative leader in 2005, it is the spectre which Cameron has desperately attempted to banish. To a point, his attempts at exorcism have been successful – but the ghost has never truly left his side.

Last Tuesday it returned to Parliament with a subtle, but no less worrying, difference. The nasty party returned, but now it has become the party of nasty surprises. This was the description used by Julian Lewis, a disgruntled Tory backbench MP, during a Commons debate on the government’s proposals to sell off the national forests.

"We may no longer be the nasty party,"

Lewis began, dragging the dreaded term back out in to the open. It then got worse still:

"But I do not want the new party that I understand some people are trying to form – a strange permanent coalition of Conservatives and Liberals – to get the reputation of being the party of nasty surprises."

The comments will have caused Home Secretary Theresa May, the author of the original "nasty party", to flinch: she has been trying to shake off the term ever since she deployed it in 2002. The question is whether Lewis' expression will match May's for resonance and durability. For it to do so, the Opposition and the media need to pin the term on to a believable narrative. Cameron will be hoping that Lewis' intervention passes by unnoticed, but his willingness to speak out against his Government is further proof of a wider unrest against the coalition’s approach to policy-formulation and direction.

This week’s meeting of the 1922 Committee – the influential backbench body of Tory MPs – was dominated by angry questions about the policy towards forestry. Where had it come from? And why, given the relatively small financial gain, was it being pursued at the risk of unrest across so many constituencies? Cameron told his backbenchers that they should be "proud" of the Government's policies, but his persuasive attempts did not prevent the Government whips flexing their muscles – and to good effect.

Only three Tory MPs voted against the government – Lewis, Caroline Nokes, and Zac Goldmsith – but in doing so a symbolic milestone was passed. As research by Professor Philip Cowley has demonstrated, there have now been 97 rebellions in the first nine months of this Parliament – one more than the total for Tony Blair's entire first term in office. The surprises have been adding up for the grumbling backbenchers.

To some extent it is a false comparison. After New Labour’s landslide win in 1997, Tony Blair acquired an army of 419 supine foot-soldiers to steer through the appropriate lobby. Cameron, on the other hand, must do his best to satisfy both Conservative and Liberal Democrat MPs. However, both are feeling that the surprises are being directed at them. Tory backbenchers have been wrong-footed by the forest plans, an announcement to delay any decision to renew Trident, and proposals by Justice Secretary Ken Clarke for the justice system to focus its efforts on rehabilitation above sentencing.

... If the anger stayed in-house, then Cameron would have little reason to worry. The frequency of rebellions is a fact of coalition life; but if the willingness to rebel starts to grow across his backbenchers, then he well soon find himself with an awkward problem. For if the anger of backbench MPs translates to the outside world, then there is reason for alarm. One in four people are said to back the health reforms, the great forest sell-off is causing angst up and down the country, and Clarke’s prisons reforms have sent the Sun newspaper into range.

So what the prime minister doesn’t need is a memorable term to group his policies together, one which reminds voters of a darker past while also providing a damaging contemporary twist. Unfortunately for Cameron, the "party of nasty surprises" seems to fit the bill nicely. He will be hoping that Julian Lewis' turn of phrase proves to be a little less haunting than Theresa May's.